Electrical mechanism and wiring circuits therefor



y 1945- c. E. ARMSTRONG 2,379,356

ELECTRICAL MECHANISM AND WIRING CIRCUITS THEREFOR Filed April 25, 1941 II I w U n 2/ Patented July 10, 1945 ELECTRICAL MECHANISM AND WIRINGCIRCUITS THEREFOR Charles E. Armstrong, Portland, Oreg., assignor toArmstrong Heat Oreg.

Control 00.,

Portland,

Application April 25, 1941, Serial No. 390,292

2 Claims.

This invention relates to improvements in electrical mechanism andwiring circuits therefor, whereby a control valve, such as is used insteam lines and water lines, can be opened and closed by a two-wirecircuit in place of the usual threewire circuit.

The conventional type of motor-actuated valve which provides for twopositions, one open and one closed, is operated by a three-wire circuitin combination with any ordinary timing mechanism operatively associatedwith the valve actuating gears. In this type of control, a common wirein contact with one of two other wires will cause the valve to close;and this common wire, in contact with the other of said two wires, willcause the valve mechanism to open the valve. In other words, one circuitis completed to the motor for closing the valve; and the breaking ofthis circuit, and the making of another will cause the valve to move tothe open position. This is common practice and has been in use for manyyears.

In contrast to the foregoing, the principal object of my invention i theprovision of simple, eflicient, and positive means for opening and/orclosing said valve with a two-wire circuit. Closing a supplementalcircuit within the two-wire circuit will actuate the motor-driven valvemechanism until a timing mechanism stops the valve in an open position.Breaking the one supplemental circuit and closing another will actuatethe motor-driven valve mechanism to return the valve to a closedposition.

A further object of this invention is to provide electric means wherebyany two-position motorized valve may be opened and then closed with asimple make-and-break type thermostat where heretofore a single-poledouble-throw type thermostat must be used-on the three-wire circuitcontrol.

The advantages of the two-wire controlling circuit over the commonthree-wire circuit are numerous in the temperature control field. Itwill be shown in the drawin how, with a'twowire circuit, any number ofthermostats may be installed in a building, and how all of them areconnected in parallel on the main two-wire control circuit; and, by thisarrangement, any one thermostat can open the valve; but, it requires allthermostats to close the valve.

It will also be shown where, under some requirements, some of thethermostats may be set in series, and others in parallel, thus makingthe one thermostat placed in series act as a master,

or high-limit control of the other thermostats which are set inparallel. 1

These and other objects will appear as my invention is more fullyhereinafter described in the following specification illustrated in theaccompanying drawing, and finally pointed out in the appended claims.

In the drawing:

Figure 1 illustrates the invention operatively applied to a conventionalmotor and gear mechanism employed in an ordinary two-position motorizedvalve.

Figure 2 shows an arrangement of thermostatic controls employed tocontrol an indirect heating system.

Referring now more particularly to the drawmg:

With reference to Figure 1, reference numeral l indicates an electricmotor which, through its shaft 2, a worm 3, and worm gear 4, drives atrain of gears (not shown) to drive a shaft 5 to which is secured a camwheel 6. The cam wheel 6 rotates in the direction of the arrow shown,and is formed with a lobe I. The train of gears driven by the motor Ithrough the worm and worm gear is contained within the housing 8, uponwhich the motor is mounted by means of the bracket 9. The housing 8 issupported upon a bracket II), which is secured, as at II, to a valvebody 12 disposed within a steam supply line I 3, and adapted to controlthe flow of steam there'- through by means of a valve l4 whose stem 15is pivotally connected, as at IS, with a link I l. The opposite end ofthe link is pivotally connected, as at [8, with the cam wheel 6, so thatrotation of the cam wheel will impart reciprocal movement to the valvestem 15. In the position shown, the valve is closed; and, upon rotationof the cam wheel 6 through degrees from the position shown will open thevalve. The link I1 is preferably of the yieldable type, formed of twohalves slidably joined together and having a spring I9 disposed betweenthe halves to compensate for any excessive pull on the valve stem beyondthat required to seat the same. The opening and closing movements of thevalve are thus controlled by the operation of the motor I which rotatesintermittently and progressively in one direction, and need not bereversible. A circuit consisting of wires 20 and 2| extends from asource of electrical energy, and the Wire 2| connects with the motor Iat its binding post 22. A branch wire 23 connects with the wire 2| andthrough binding post 24 to one side of a thermostat 25, having contacts,26 and 21. The contact 21 connects by wire 28 through a binding post 29with one side of a magnet coil 30, whose opposite side is connected bywire 3| with the wire 20, back to the source. The wire 20, by extension32, connects with one end of an armature 33, forming a part of asingle-pole-dou-ble-throw switch including contacts 34 and 35 betweenwhich operates a contact point 36, carried by the armature. The contact34 is connected by wire 31 with one arm 38 of a circuit breaker having acompanion arm 39. Both arms are yieldingly interconnected by a spring39A and pivotally mounted, as at 49, to

the lower end of the housing 8, and separated by suitable dielectricmaterial. The upper ends of the arms, 38 and 39, carry contacts, 4| and42, respectively, which are adapted to make and break with contacts 43and 44, respectively, carried by a buss bar 45 which is mounted, to andinsulated from the upper end of the housing 8. The buss bar is connectedby wire 45 with the opposite-binding post 41 of the motor The contact 42at the upper end of the arm 39 of the circuit breaker is connected bywire 48 with the contact 35 of the single-pole-double-throw switch.

With the parts in the positions shown in Fig" ure 1. the valve l4 hasbeen moved to a closed position by rotation of the cam wheel 6 into aposition where the lobe T has contacted a projection. or an enlargement49, on the arm 38 of the circuit breaker which moves that arm to theright, as viewed in Figure 1. and thereby breaks the circuit throughwire 31, buss bar 45, and wire 46 back to the motor. Breaking of thiscircuit, of course, stops motor operation and allows the valve H toremain in a closed position to stop the supply of steam to the spacebeing heated until the temperature therein drops to a predetermineddegree to cause the contacts, 26 and 21, of the tbermostat 25 to cometogether to close the circuit through Wire 23 back to one side of thesource, and through wire 28, through the magnet coil 30. thence back tothe other side of the source. Energizing the magnet coil, of course,draws the armature 33 and its contact 36 downwardly and away from thecontact 34 and into contact with contact 35, whereupon a circuit is thencompleted from one sid of the source through wire 20, through thearmature 33, contact 35, wire 48. and through the contact 42 of the arm39 of the circuit breaker into the buss bar 45, thence through wire 46into the motor, and from the motor through wire 2| back into the otherside of the source. Thus, energy is again supplied to the motor to causeit to operate until the cam wheel 6 rotates again through 180 degrees tomove the valve |4 through its stem l5, and the link into an openposition. This amount of rotation of the cam wheel 6 also causes thelobe I to move out of contact with the arm 38 of the circuit breaker,and into contact with the pro jection 50 on the arm 39 of the circuitbreaker. This contact of the lobe l, with the projection 50 moves thearm 39 outwardly a sufficient distance 'to separate the contacts 42 and43 to again break the circuit to the motor extending through wire 48,contacts 35 and 36, now closed by energize.- tion of the magnetic coil30, thence through wires 3| and back to the source. The opposite side ofthe motor, of course, is connected with the source through wire 2|,running direct to the binding post 22. The opening of the valve 4 will,of course, supply steam for heating the space within which thethermostat is disposed, and will cause the thermostat to resume asatisfied position, at which time, the contacts 26 and 21 will beseparated to break the circuit through wire 23 back to one side of thesource, and through wire 28, coil 30, wires 3| and 20 back to theopposite side of the source. Breaking of this circuit de-energizes thecoil 30; and by means of the coil spring 5|, the armature is swunupwardly around its pivot point 52 into a position to again close thecircuit from one side of the source through wire 2|], branch wire 32,armature 33, contact 34, wire 31, back into contact 4| of arm 38, thenthrough wire 48 into the motor. the opposite side of which, of course,is connected with the opposite side of the source. Thus a circuithasjbeen re-established to the motor whereby it is again ready to beoperated by the demands of the thermostat 25 upon the closing of itscontacts, 26 and 2-1; which will occur upon a drop in temperature.

In Figure 2, I have shown the steam line l3 connected with any approvedtype of heating coil 53 disposed within an air delivery duct 54 in opencommunication at its end 55 with a space to be heated. Th opposite endof the delivery duct is provided with a suction fan 56 driven by anysuitable means, such, for instance, as an electric motor, or the like.The fan housing is in open communication by means of the aperture 51with an air intake duct 58 extending through the roof or wall of abuilding to the atmosphere. Operation of the fan will draw fresh airthrough the intak duct; and by means 01" the fan, the air will be forcedthrough the heating coil 53, through the delivery duct 54, and into thespace to be heated. Within the delivery duct and arranged in advance ofthe heating coil are two thermostats, 59 and 60. The thermostat 59 mayhe referred to as a high limit thermostat, and the one at 50 may bereferred to as a low limit thermostat. Disposed within the space to beheated is a room thermostat 6|. It will be noted that the high limitthermostat 59 is connected in series with -a circuit extending to asource of supply consisting of a control circuit C comprising wires 62and B3 connecting binding posts 64 and 65 which may be the same bindingposts 24 and 29, respectively, shown and described in connection withFigure 1, so that the mechanism of Figure 1 may be controlled by any oneof the three thermostats 59, 60, and BI in the indirect heating system.The high limit thermostat 59, being connected in series with circuit C,will render the thermostats, 60 and SI, ineiiective at an extremely hightemperature, for example, F., at which the thermostat 59 may be set toopen. In the temperature range below 140 R, either of the thermostats,50 and 6|, connected in multiple with the circuit C may actuate the valvmechanism to supply more steam to the system. For example, thethermostat 60 may be set to remain closed. at any degree below 68, andopen at any degree of temperature thereabove, while the thermostat 6|may be set to close at temperatures be low 70 F., and to open above thatdegree of temperature. Thus, if the temperature of the incoming heatedair is less than 140 F.. and the circuit C is complete up to boththermostats. B0 and GI, by reason of the thermostat 59 beingclosedyeither thermostat, 60 or 6|, may retain the steam supply valve Min an open position to supply steam to the system, When needed, at theirrespective locations. For example, if the temperature in the locality ofthe thermostat 6| is below 70 F., and the thermostat closes, the controlcircuit will be completed to the binding posts,

perature rises above 70 F., regardless of the attitude of the thermostat60. If, on the other hand, the temperature in the air delivery duct,

which influences the thermostat 60, should drop below 68 F., it willcause the thermostat 60 to close and operate the steam supplyingmechanism regardless of the attitude of the thermostat 6 I.

In Figure 3, I have illustrated a plurality of thermostats 66, 61, and68, all connected in parallel with a control circuit D, connected withterminals 69 and 10 which may also be the equivalent of the terminals 24and 29, shown in Figure 1. Each of the thermostats 66, 61, and 68 are ofthe simple make-and-break type with their contact points so arrangedthat they will close upon a drop in temperature and open upon a rise intemperature.

Each thermostat may be placed in difierent remote locations throughout abuilding or structure to be heated. The purpose of this arrangement isto insure that all parts of the building will be heated to the desiredtemperature before the steam valve will be closed to cut off the supplyof steam. By this arrangement, the part of the building bein exposed toa prevailing wind or any other cause necessitating more heat thanrequired in the other parts, the control is auto matically establishedat this point. For example, if the temperature surrounding thermostats61 and 68 were to rise sufliciently to open the contacts in both ofthose thermostats, and if the temperature surrounding thermostat 66remained below the desired temperature, then contacts in that thermostatwould remain closed to maintain the circuit closed through binding posts69 and 10 which, in turn, through the mechanism described in Figure 1,will hold the steam valve in an open position to continue the supply ofsteam. But, when the temperature surrounding the thermostat 66 isbrought up to open those contacts, the control valve will then close.Thus, a temperature drop at the location of any of the thermostats, 66,61, 68, or any number of them so connected in the control circuit willpick up the control of the steam valve.

While I have shown a particular form of embodiment of my invention, I amaware that many minor changes therein will readily suggest themselves toothers skilled in the art without departing from the spirit and scope ofthe invention. Having thus described my invention, what I claim as newand desire to protect by Letters Patent is:

1. An electrically operated device, comprising an electric motor, a gearmechanism, two mechanically operated electric switches, an electricrelay having two switches; one of said relay switches being normallyopen; the other of said relay switches being normally closed; twoelectrio circuits, a thermostat disposed at a remote station, said motoroperating said gear mechanism, said gear mechanism operating said twomechanically operated switches, said electric relay being operated bysaid remotely stationed thermostat, said motor and said two mechanicallyoperated switches and said two relay operated switches being embracedwithin one of said electric circuits, said relay and said remotelystationed thermostat being embraced within the other of said electriccircuits.

2. An electrically operated device, comprising an electric motorconnected in a circuit to a source of electrical supply through anelectric relay, said relay also being connected to said source of supplyand having two switches associated therewith and operable thereby, apair of switches operatively connected with said motor and adapted to beopened and closed thereby, said pair of switches being electricallyconnected with the switches of the relay whereby, current from thesource may be alternately directed to the motor by operation of therelay switches, a two-wire circuit extending from the relay to atemperature sensitive switch remotely disposed from the device to thesource of supply whereby closing 01' opening of said switch will actuatethe relay to direct current to the motor for a predetermined length oftime.

CHARLES E. ARMSTRONG.

